Joe's 2006 in Boise ID [Archive] - CNCzone.com-The Ultimate Machinist Community

gacrwell

02-17-2007, 11:50 PM

Progress Report, 1-week post CNC commitment:

Purchased Hitachi router, $119, local Lowe's.
Ordered Joe's full kit, ~4 weeks delivery.
Ordered HobbyCNC PRO 3-axis controller, $79.
Ordered Keling steppers: KL23H286-20-8B x3 $54 ea.
Ordered bearing sets from vxb.com, $45.
Did my taxes, two months early!I had pretty much decided on the HobbyCNC PRO controller, but I wanted to look at user's experiences with it on their Yapoo user's group. But, you can't find that group on Yapoo by searching: it's literally invisible. I finally did find the group via a link posted here on CNCZone: http://groups.yahoo.com/group/hobbycnc/ Wasn't surprised to find out it's members only, so I asked to join. Twice. Denied. Twice. What kind of brain-dead marketing is this? It turns out that only after you place an order, are you given the above link, and then your membership will be approved. Oh well, it was still the controller I wanted. After ordering, applying (3rd time), being blessed, and reading through the group, I found that someone had good luck with the Keling motors, so those were what I ordered.

On the bearing sets, one was $5 more than the price listed in Joe's instructions, and one was $5 less, so that was a wash. However, upon checkout, on orders over $30 there was an offer of 8, free, 8x22x7 bearings, so I've got those extra FWIW.

Some of the other stuff on hand:

Plenty of old assorted PC's, monitors, keyboards, parallel cables and stuff.
An old industrial rack mount PC case that I'll stuff one of those PC's into.
A monster of a surplus switching power supply.
An old metal equipment cabinet that should house the power supply and controller.
I also just picked up a nice little 100MHz oscilloscope for $75; a steal - the guy I got it from had paid over $200 for it on ebay, and that wasn't a bad price. Might come in handy for troubleshooting.That old power supply has three 15V outputs and one 5V, all at least 16A. Combinations of those should allow output choices of 15, 20, 30, 35, 45, or 50V (I’m thinking 35 would be a good place to start with the HobbyCNC.

Before the motors and controller arrive, I need to stuff a PC into the industrial case, get it set up, and test the stepper power supply. Then I'll be ready to test the controllers and motors on the bench when they get here. Have to get the software downloaded and set up too.

Still waiting on a couple of shopping trips to check out local availability of the rest of the hardware before making an order to use-enco, and the nuts&bolts place. I'd like to have the bearing angles fabricated before Joe's kit gets here.

After reading about the dozens of rattle cans that some of you have used for painting, I think I'll pick up a cheap (costco/harbor freight) spray gun and try that. Wally world has Kilz primer in gallons for $10, and Rustoleum colors for ~$7 a quart. I really liked the white/grey/blue color scheme that I've seen here.

Also looking at cable and connectors, expensive. Might have to pass on what I want for now. ebay wasn't any help. Haven't looked at surplus places yet, they might at least be good for the limit switches.

I don't have a shop-vac yet either; I'm open to suggestions.

I went out to James' house this afternoon to see his Joe's. (Hmmm, put that way, it sounds vaguely dirty.) Learned a lot and it was very enlightening to see one in the flesh. (Oops, still sounds dirty.) You guys should get yourselves in the pictures more often (like - at all - I don't think I've ever seen an actual person in the build photos here), to provide a sense of scale of the thing. I described it to my wife as "a big FoosBall table".

Turns out James and I only live about 10 miles apart and have very likely met before; our respective employers do business with each other.

One other task before stuff starts arriving - I have to make a Joe's CNC-sized clear space in the garage somewhere. The stack of blue astroturf may have to go (James knows what that is; I should take him a piece.)

Gary

ccsparky

02-18-2007, 07:22 AM

Hello Gary,

Welcome, looks like you've got a pretty good jump on it.

That's really great that you and James live so close to be able to check out his build. Like Dwayne said, the people here are really great.
I have read each persons log several times and still get a kick out of what everyone has done... very creative people!

Enjoy, and look forward to seeing your progress!!! :)

Bob

gmfoster

02-18-2007, 07:51 AM

[QUOTE=I had pretty much decided on the HobbyCNC PRO controller, but I wanted to look at user's experiences with it on their Yapoo user's group. But, you can't find that group on Yapoo by searching: it's literally invisible. I finally did find the group via a link posted here on CNCZone: http://groups.yahoo.com/group/hobbycnc/ Wasn't surprised to find out it's members only, so I asked to join. Twice. Denied. Twice. What kind of brain-dead marketing is this? It turns out that only after you place an order, are you given the above link, and then your membership will be approved.

The group is not for marketing. And I for one sure wouldn't call Dave brain dead. The group is for customer support, he seems to get about all the customers he can handle and limiting his support forum to customers makes a ton of sense.

Garry

Jay C

02-19-2007, 11:09 AM

Also, if you wanted user feedback, there is a HobbyCNC forum here too :) Do tell more about this monster power supply though. And a 4U rack case is huge! You ought not have any issues finding space :)

Pictures please :)

pen25

02-19-2007, 12:23 PM

gacrwell

02-20-2007, 01:32 AM

Here's the rack mount PC chassis. It was intended for a test equipment station at work, but they finally went with 1U server-type PC's and this case was up for grabs. The reset, power switch, and disk drive bays are behind the latching door. The white square sitting on the door is the cleanable, replaceable fan filter. The pity of it is, I also had a 19" half-rack that would have held this and the controller box & power supply, but I tossed it last Fall.

The power supply is an old Power-One, with plug-in modules. The first is the AC front-end. The second has dual 15V, 16A outputs; the third is 15V @ 33A, and the forth is 5V @ 80A. I'm pretty certain all of the outputs are floating, so I should be able to wire those up in the combinations I mentioned earlier.

Sagan says hi.

Gary

gacrwell

02-25-2007, 10:33 PM

Progress - 2 weeks in:

The Keling motors arrived
The HobbyCNC Pro arrived
The vxb bearings arrivedThough the HCNCP arrived almost a week ago, it took awhile to get around to building it. My interest in it was the SLA707x drivers that it uses - I'd like to fiddle with some driver ideas with them myself, so I first took the time to back out the schematic, and it's easier to do that off the bare board. Turns out to be not much different than the SLA706x driver board at pminmo, or what's on the data sheet for that matter. I may use the empty 4th axis of the board as a breadboard site. I also ordered some extra SLA chips.

The HobbyCNC PRO assembled with no problem, checked out and set the reference voltages, but haven't hooked up the steppers/PC yet - will get to that this week.

I didn't like the idea of having to template off the board to drill the heatsink holes, so I made up a dimensioned sketch of the board and HS... but my CAD program crashed when I saved it, so I get to redo that tomorrow. I'll post it here when done. I figure that the reason Dave doesn't supply a drilled heatsink or a drawing is that the driver positions can vary too much depending upon the installation. But that's easy to fix. Fabricate the heatsink first, then insert the drivers in the board without soldering, screw them to the heatsink, - now everything's aligned without stress - and finally solder the pins. The driver positions can also vary because the pattern of the driver pin holes in the board are 25 mils off - makes them harder to insert than necessary. The board was laid out well for kit assembly though - the orientations of all the polarized components were identical.

Haven't had much luck finding hardware and other materials locally, so I'll be ordering that and the acme stuff this week.

Gary

gacrwell

02-27-2007, 01:23 PM

Here's the sketch of the heatsink dimensions for the HobbyCNC Pro. This also includes the board outline and its dimensions.

Edit: BTW, I have found a finned heatsink extrusion that would be excellent for the HobbyCNC PRO; smaller and more effective than a solid bar. I'm getting a quote to see if it's cost effective.

My extra SLA7078's arrived today, and I'm working on a schematic of a power supply to replace the linear regulators on the CNC PRO - I've always thought it should have a 12V output so you could use a regular PC fan.

Gary

gacrwell

03-03-2007, 09:54 PM

Progress – 3 weeks in:

ordered the nuts & bolts
ordered the acme rods & angle aluminum
ordered cable
bid on limit switches
locally purchased glue & vinyl hoseThe nuts & bolts I ordered from www.BoltsDepot.com (http://www.boltsdepot.com/) using the list of hardware that appeared in the original Joe’s thread. The full order is shown in the attachment below. The only changes were that some of the prices increased (naturally); for about fifteen cents more I changed the quantity of 1/4" flat washers to a 100/box, and I included U-bolts, that I think are the right size. These U-bolts are more expensive than the Amazon link that someone mentioned, but the shipping there is a killer.

The www.use-enco.com (http://www.use-enco.com) order is also attached below. It's also the same as what was listed in the Joe’s thread, except that I added the aluminum angle, two 48” pieces @ $10 each. I never ran across that size locally.

This guy: jcoenterprises, on ebay, seems to have a lot of various cable for reasonable prices. I bought 115 ft of 18 gauge, 6 conductor for about $30 plus $15 shipping. I’m sure that’s three or four times what I’ll use, but I may resell the rest. Still looking for some light, shielded, 2-conductor cable for the limit switches.

I’ve bid on a 50-count lot of micro-switches on ebay, that’s why I can’t post this until it closes, else one of you fine fellows might snipe it away. Actually it’ll probably get outbid anyway, ‘cause there’s not much margin and I don’t want to go higher. If that doesn’t work, www.allelectronics.com (http://www.allelectronics.com/) has several roller switches that look good in the $1.50 each range. Also, this guy: carolbrent (dba Hubbard CNC Components) on ebay, has switches in sets of three for $3.29 and reasonable shipping, They also have some reasonably priced 6-pin connector sets that look pretty good, but I’m still looking around.

About all the local hardware stores were good for was the 16oz bottle of Titebond III (wondering if that’ll be enough), and the vinyl hose. I’ll probably wind up buying the ¼” allthread and gas pipes at the local Lowe’s or HomeDepot too. Also picked up a couple of corner clamps (I’m sure I’ll need more) and a cheap palm sander at Harbor Freight.

Preparing to hook things up to try spinning the motors. I knew I had a box of parallel cables, but when I opened it, sure there were cables, but all Centronics printer cables. I'd completely forgotten those used to be the 'standard' parallel cable type. Not a DB25M-to-DB25F in the bunch. (I have noted that at least one motor controller uses a Centronics connector, but I've also noted why most don't: expensive connector.) Stopped at the local computer store - I could have bought one there for $10, but they had a solder cup DB25 and hood for $2 - I needed the soldering exercise anyway; so I cut off the Centronics connector and with a little soldering, now I have a cable. (Yeah, I've seen those cables on-line for $3-$4, but there's the wait, and shipping.)

Put a line cord on my power supply, and checked it out: all the voltages are there. Tried putting the two 15V outputs from the same module in series, but it didn't seem to like that, no output, so apparently those two aren't floating with respect to each other. But, it didn't appear to have hurt anything. Using one of those 15V outputs in series with the other 15V module gave 30V OK. I could also use the third 5V module to get up to 35V. I notice I'm going to need a line input module and switch for this thing. Still haven't hunted down the cabinet that I think is in the garage, that should be large enough to house the power supply and controller.

Ordered some sample parts and did some schematic sketching on the controller that I'll build to replace the HobbyCNC PRO. For the moment, I'm calling it vCNC. The HCNCP runs the signals from the PC straight to the driver ic's, which also have the motor voltage on them. I don't trust things that much, so I'll at least buffer those lines with a cheap sacrificial chip, sort of a mid-way compromise between opto-isolation$$ and running naked. Easy to make that 3.3V compliant too. The switch lines back to the PC are also 'naked', and that's asking for ESD damage to the PC, so I'll buffer those too. The 'charge pump' gadget is also easy to add.

Well how 'bout that; nobody sniped the switches. Got them for about 70 cents each, with shipping. 'Course that's about 5x more than I need. Hoping they're usable.

Gary

ccsparky

03-03-2007, 10:34 PM

It's like the home shopping network around here ;)

Thanks for the info. I just ordered some cables and need to purchase some two conductor also.

Any pics of your progress?

Jay C

03-03-2007, 10:50 PM

The www.use-emco.com order is also attached below. It's also the same as what was listed in the Joe’s thread, except that I added the aluminum angle, two 48” pieces @ $10 each. I never ran across that size locally.
BTW, it's use-enco.com not emco ;)

gacrwell

03-04-2007, 01:29 AM

BTW, it's use-enco.com not emco ;)

Oh gosh, I wonder who I ordered from then? Be funny if I got a truckload of flower pots or something... But thanks, I seem to have a mental block about that enco-emco thing.

I'll have pics of the motor/controller/ps when I get them spinning. I still have to d/l and install some driver s/w.

Gary

gacrwell

03-04-2007, 04:08 AM

Finally did find a place that sells shielded multi-conductor cable by-the-foot, that looks good for limit switch connections: www.altex.com (http://www.altex.com)

I actually ordered the 4-conductor, rs-232 cable, shielded. Specifically: http://www.altex.com/product_info.php?cPath=3_10_101&products_id=1620

At 0.18/foot it's about the cheapest they've got, and I figure many of the switch connections can be ganged in the same cable (rather than run a single 2-cond cable back to the controller for each switch). It bothers me a bit now that I notice the description doesn't specifically state that it's stranded - guess I'll find out.

As ever, the shipping cost makes it a not-so-great deal. I'll report on the quality/suitability of the stuff when it shows up.

Gary

bp092

03-04-2007, 08:58 AM

Sounds good Gary, bolt depot rocks, it's a small business and they are very helpfull and personal.. plus everything is sep. bagged and labeled neatly. It's the cheapest way to go, HD Is a waste of time, they don't even sell larger full thread bolts anymore. Also anyone that used BD be sure to up your quantities to full 100 boxes sometimes. I believe I posted the pic in joes thread, but I did the math on a few and it's actually cheaper to buy a box then sep. in the higher quantities, plus then you have extras :D.

gacrwell

03-04-2007, 12:21 PM

... Also anyone that used BD be sure to up your quantities to full 100 boxes sometimes....:D.

Yep, I see I should have done that with the #835 1/4-20 x 2; $7 vs $4 would have been worth getting 3x as many - useful size too.

On all of this stuff you could save a ton if you could share with a local partner(s) who was also doing a build, to save on shipping and bulk discounts.

Gary

gacrwell

03-10-2007, 03:25 PM

ON CONNECTORS:

I was really surprised when I started reading on CNCZone, that there apparently isn't a common motor connector type in use. Everyone just gets to hunt down whatever fits that they can afford. I guess DIN connectors are used pretty often, but few seem to admit it; whenever DIN is mentioned, someone pops up saying that they aren't really for high current and the quality is poor. Some mention D-subs, but I dislike those even when I have to use them on PC ports. So, apparently like everyone before me, I started my connector search. Apologies in advance for the length, I just rambled on.

The first consideration is going to be the motor and controller you're using. My controller is unipolar, so that means at least 5 wires. I've got 8-wire motors, but two wires of each pair of coils are common, so they can be served by six wires in the cable. The common points of the two coil pairs could also be connected together, requiring only 5 wires, but that puts all the return current in one wire and I don't think that's a good idea; so six wires. The wires coming out of the motor are 22AWG, for a 3A, 23-size motor. While 22 gauge would probably work, those wires weren't intended to run the 10 feet or so back to the controller, and, I might like to upgrade the motors in the future, so I think a larger gauge for the cable is prudent. When I was searching for cable, 20 gauge seemed pretty uncommon (odd wire gauges are right out), so 18AWG seemed like a good choice. The cable I finally bought (at a pretty good price) looks huge: the outer jacket is 0.425" in diameter. I doubt that any 6-wire, 18 gauge is ever going to be much smaller.

I'm assuming that it's desirable to put a socket on the cabinet housing the controller, and a connector pair at the motor. They don't absolutely have to be the same style of connector, but if they are, it allows the motor to be plugged directly into the controller for testing, without an intervening cable. So a panel mount version of the chosen connector is a pretty stiff requirement.

So those considerations and other needs define my connector requirements:

readily available from multiple sources, and in stock.
6 circuit, (7, 8, or 9 is acceptable)
18-22AWG
5-12A/pin
durable, >100 mating cycles desired
selection of genders and mounting styles
>0.425" cable entry (>10mm)
positive latching
polarized
fully shrouded pins
reasonable costCircular Connectors:

Any Amphenol connectors are too expensive.
Switchcraft ENC styles are priced on the high side, but include everything; connector, pins, cable shroud; but don't accept a cable dia over 6.5mm.
AMP CPC: Similar to the Switchcraft ENC and probably about the same price after adding up all the parts, but they don't accept a cable over 0.3". (On both the ENC and CPC, it may be possible to hack up the shroud to fit the cable, or just leave it off.)
And that's about it; everything else I've found is way too expensive.Besides the expense, the major difference between circular and rectangular connectors is durability: When it is specified, it's usually listed as some number of mating cycles (before it goes out of spec for contact resistance). The circular connectors I've looked at report cycles in the range of 200-600. That's what you're paying for. The much less expensive rectangular connectors, when they report a durability figure, are in the range of 20-50. You're going to have to ask yourself realistically how often you expect to be cycling the connectors - maybe rectangular connectors will be unsuitable, or perhaps the expense of circular connectors is unnecessary - depends on what you're doin'.

Anyway, I didn't find any circular connectors that would fit, that I could afford. So on to the open-type rectangular connectors. But first:

A word on connector pin current: When a connector mentions maximum current, that's the maximum continuous current per pin, that produces an acceptable temperature rise, on that single pin. When connector pins are placed in a common shell, even if they are electrically isolated, they will heat mutually, attaining the temperature limit much quicker. A 6-pin connector, that is rated at 10A/pin will not carry a total of 60 Amps; 20 may be the practical limit.
Another word on connector pin current: Parallel pin current ratings are not additive. That is, two 3A pins ganged in parallel will not reliably carry 6A. Small variations in contact resistance can unbalance the current in shared pins dramatically, causing one pin to carry more than its rated current. It's common practice to derate the current spec with pins in parallel. The more pins in parallel, the greater the derating per pin. 2 pins, derate by 20%; 3 pins, derate by 30%; four pins, derate by 35%. Those values are approximate, from memory. But, in general, you don't gain anything in current capacity by ganging smaller pins, that isn't better served by a single correctly sized pin.
A word on connector pins: On most of these connectors the contact pins are purchased separately and inserted into the connector housing after the wire is crimped onto the pin. Pin prices vary from about 10 to over 70 cents per pin. With 6 pins/connector, the pin prices often outweigh the cost of the connector shell. The less expensive pins are usually tin, tin-lead, brass, or phosphor-bronze. Mid-cost are gold flash, and the most expensive are some variety of thicker gold. First rule: don't mix pin types. Mate tin-to-tin, or gold-to-gold etc. Second, if you are going to mate-dismate the connectors more than a few times, don't bother with gold flash - it'll be worn off after a couple of cycles.
And also, when crimping wires into connector pins, do -not- tin stranded wire.Rectangular Connectors: The overall cable diameter doesn't matter with rectangular connectors, because there's no cable shroud or
strain relief - this is not a good thing, but it's what you're pretty much stuck with in the realm of rectangular connectors.

Molex Micro-Fit - doesn't take wire sizes larger than 20AWG
Molex Mini-Fit Sr - doesn't take wire sizes smaller than 14AWG
Molex Mini-Fit Jr - I've used MFJ's in dozens of applications, and never had a problem. However those applications were usually inside boxes, and didn't involve repeated connection cycles. They are inexpensive, ubiquitous, and available in the widest variety of styles. But most people don't seem to like them; they sometimes have problems with pin retention, and they can be difficult to unmate sometimes.
Molex MX150L - I've never seen these in the flesh, but they look neat in the catalog. More expensive than other rectangular connectors, but the connection interface is sealed - more like circular connectors. Unfortunately they are cable-to-cable free hanging only; no panel mount version.
Molex MLX 0.084" - really plain, super cheap. They'd probably work. No option for gold pins.
Molex Standard 0.062" & 0.093" - friction latch only, wouldn't trust 'em.
AMP Commercial MATE-N-LOK - These are another fairly vanilla rectangular connector except for one thing. I distinctly recall seeing one a few years ago and fiddling with the dual latch that is on the 6, 8 and 10 circuit dual row (not matrix) style of this connector. I was impressed with how positive and easy to operate the latch was. Pins are available in a wide range of AWG sizes and contact finishes. The shells are cheap, total cost depends on how much you want to spend on pins. Free-hanging or panel (they call it motor) mount; and a vertical pcb header too.Surplus/other connectors: Good luck, you might find a gem. The only drawback is that you might find it impossible to get more of the same in the future, should the need arise. I've mentioned before, HUBBARD CNC COMPONENTS, on ebay. They have four and six pin connector sets, that are inexpensive and look really good in the picture. 18AWG, 20A/pin, positive latching. I don't recognize the specific model/manufacturer - this worries me about future availability, and, no apparent panel mount version.

I may inquire about the Hubbard, but for the moment I'm considering the MATE-N-LOK. I also might think about the AMP CPC without the cable shroud. I'd appreciate any comments or other ideas and suggestions.

Gary

David Da Costa

03-10-2007, 04:30 PM

You seem to have ruled out no connector and just connecting straight to the controller which is what I ended up doing after trying DIN connectors.

I think the reality is once all tested you are unlikely to want to disconnect the motors from the controller very often and when you do it is not to much work to just disconnect the cables from the terminal blocks.

David

David

jspencer

03-10-2007, 04:58 PM

Hey Gary, did you get the switches yet and if so are they any good?

James

gacrwell

03-10-2007, 10:53 PM

Progress – 4 weeks in

The Bolt Depot order arrived.
The USE-ENCO order arrived with the acme rods, Lovejoys and aluminum angle.
The 6-conductor 18AWG cable that I got on ebay arrived.
The shielded 4-conductor 28AWG cable from altex.com arrived.
The micro switches that I got on ebay arrived.
At this point the FedEx and UPS guys are really wondering what’s going on.Other than the kit from Joe, and maybe some connectors, that should be everything that’s coming by mail. All that should be left to buy are the gas pipes, some allthread, the ¼" skins for the table, and whatever I’m going to paint it with.

Both of the cable types I got look excellent and I think the price/foot was good, though in both cases I’ve probably got 3x what I’ll need for this build. I haven’t got the cable routing planned out, but I think the 4-conductor will work out well – that’ll give 2 wires for a limit switch loop and 2 for the home switch per axis.

The micro switches look good; smaller than I expected, but that shouldn’t be a problem. I got a set of them over to James tonight so he should be giving them a try long before I can. I see the same guy has another lot of 50 on ebay now: http://cgi.ebay.com/Micro-switches-with-Roller-Lever-switch-250V-5A-50ea_W0QQitemZ230102715590QQcategoryZ50916QQssPageNameZWDVWQQrdZ1QQcmdZViewItem (http://cgi.ebay.com/Micro-switches-with-Roller-Lever-switch-250V-5A-50ea_W0QQitemZ230102715590QQcategoryZ50916QQssPageNameZWDVWQQrdZ1QQcmdZViewItem) If that link doesn’t work, the seller’s name is pm-sam. Starting bid is $20.50, buy-it-now for $30, shipping is $7.50. They come with a little 2-pin 100 mil, latching connector installed on the 20” wire leads – might be able to use that.

I didn’t get to do much of anything this week, ‘cause I had an online class I had to finish or else I’d have to eat the tuition. But that’s finished now. I actually did just make my very first cut on the aluminum angle, with my old wobbly radial arm saw. On the third try, I think I did get it figured out, and made a nice cut. It’s too late to continue annoying the neighbours tonight, so I’ll get out there bright and early tomorrow to finish cutting.

I finally did download and install Mach3, and fiddled with it a bit. I need to install it on a different PC, then I’ll try the motors and controller. I also did a bit more on the schematic for the vCNC controller; just a few details to fill in – I’ll attach it.

I never did find the cabinet that I was planning to put the power supply and controller in, but while looking I ran across another cabinet that I’d totally forgotten about. It’s probably even better than the one I was thinking of. It’s an old S-100 computer chassis that someone gave me. I’ll get pics of it later. The neat part about it is that after I strip out the backplane and old linear power supply, it will still have a fused power input plug and power switch that I can wire into my switching supply. It has a fan too.

I was sure I had an old solid-state relay module here somewhere that I was going to use for the spindle control, but it hasn't turned up yet. Might have to find something else.

Gary

gacrwell

03-14-2007, 01:03 PM

OMG, just got an email from DHL that a BFP is on the way.

Gary

joecnc2006

03-14-2007, 04:16 PM

OMG, just got an email from DHL that a BFP is on the way.

Gary

yea, they already took it and on its way. Sorry it was a few days late, I cut these out in my spare time.

Joe

bp092

03-14-2007, 07:04 PM

yea, they already took it and on its way. Sorry it was a few days late, I cut these out in my spare time.

Joe

you have spare time? where can I find such a thing? :confused: my machine has been running every night since I started cutting

gacrwell

03-18-2007, 12:16 AM

Progress - 5 weeks

The kit has shipped, and I expect it'll show up sometime next week.
Cut all the aluminimum angle bearing slides to length
Drilled the 6" slidesThe angle cut very well on my old radial arm saw. I haven't used it in years, but somewhere along the way I must have bought it a new blade. The cuts got better the more I did, so I guess the blade was getting sharper. It also worked extrordinarily well for cutting the notches. I was able to dress up and deburr the cuts on a little disk/belt sander.

For the holes, I measured, scribed, centerpunched, and then drilled most carefully. A small Harbor Frieght drill press for that, and some really nice pilot-tip bits that went thru it like butter; no wander, not a hint of snagging. But. I can't see worth a darn, and no depth perception to boot. It was really difficult to set the pilot point on the punch point, so I'm not too happy with the placement accuracy of the bearing holes.

I've only drilled the 6" pieces, so I test mounted the bearings, and set out to measure just how misaligned the bearings would be. See the pics. I set the bearing angle piece flat, set the drill rod in it, and measured the vertical displacement of the rod above the table, about a foot from the end of the bearing, then zeroed the calipers, flipped the bearing 180, and measured the difference at the same spot. Then, with a left-over piece of angle held alongside the bearing, I measured the horizontal displacement the same way. [Flipping the bearing piece and looking at the difference instead of measuring each end insures that I'm measuring error from the bearing, and not my warped table.] These were the results:

bearing #1 190mil vertical
bearing #1 88mil horizontal
bearing #2 43mil vertical
bearing #2 36mil horizontalThis is the effective misalignment over about 2 feet of run. I'm pretty happy with the second one but the first bothers me. So I'm wondering - is this a bad thing? Has anyone else tried such measurements?

After some thought, I realize that the only really critical dimension on the bearing holes is the 0.433" offset from the corner - minor longitudinal variation won't affect the alignment at all. So when I drill the rest, I'll clamp the drill press vice onto the table to set the 0.433 distance identically for all drills - even if I miss the distance a bit, it's more important that they all be identical. If they come out better, I'll probably re-do the 6".

BTW, I'm sure someone must have noted it before, but I thought I'd mention it again; on the .pdf R-2 instructions, the line on page 6:
"Each 7-1/2" bearing slides uses (4) 5 /16"x1" bolts, (8) 51/6" nuts and (8) 5/16" lock washers (one nut and one lock washer between the bearing and angle alumn.)" ... can't be right. 1" bolts aren't long enough - I'm sure that must be 1-1/2", and I think that's reflected correctly in the bolt parts list earlier in the document.

I've done some more on the vCNC schematic. The 'miracle' box is smaller now. Looking at Triac switches to include as relays & deciding what I want to do for terminal blocks/connectors.

And about connectors, while DIN are discouraged for motor cables, Mini-DIN look perfect for limit/home switch cables.

Pics are also of the old S-100 PC chassis that I'll use to house the power supply and controller. Latching, hinged top; power switch is in the upper left corner of the front panel; even has folding handles on the sides. Just remove the card cage, old linear power supply, and take care of the ferret infestation, and it'll be ready to go.

The spiffy yellow bearings in the first pic are the ones that came free with the >$30 vxb order. I don't know if they're 'better' than the others or not, but they do seem to turn more freely - I thought the Z axis would be a good place for them.

Gary

gacrwell

03-18-2007, 01:42 AM

Here's a shot of the switches I picked up on ebay. They're just over 3/4" of an inch long. I don't know that they won't work, but I would have preferred something that at least looks more robust. The terminals are too small to take faston lugs; wires will have to be soldered. And, it looks like they will need 2-56 screws for mounting. It's already wired with a 20" lead and connector, but I don't know yet if it's wired NC or NO - would be easy to change - the other terminal is there. jspencer has some of them to try on his machine - haven't heard yet how that's worked out.

I'd mentioned earlier that there was another set of 50 on ebay but someone picked them up with the Buy-it-now. But, I see that the same seller has put out another bundle of 50: http://cgi.ebay.com/Micro-switches-w...QQcmdZViewItem (http://cgi.ebay.com/Micro-switches-with-Roller-Lever-switch-250V-5A-50ea_W0QQitemZ230104814908QQcategoryZ50916QQssPageNameZWDVWQQrdZ1QQcmdZViewItem)
He may have hundreds/thousands of them.

Gary

bp092

03-18-2007, 08:44 AM

lol, your ferret might get a nice shock if he decides to find his way back in there while you're machining something

For the switches most have writing on one side or it's molded in there. Typically one will go on the side, and then the two on the bottom are NO and NC. You can test it with a circuit meter if you're still unsure, just by clicking them until you find which one you want. IE: closing the switch makes a complete circuit, or it doesn't.

I actually broke 2 on my z before I set them up because I wasn't paying close attention. They were smaller like yours anyways. I would get something a little beefey, otherwise they are a pain to mount, especially in mdf. Yours are prewired though, kind of a plus. I wired mine and used the same clips that david used, crimp on connectors. They slid over the prongs pretty good but came out after a little while. Had to affix them later on.

jspencer

03-18-2007, 10:15 AM

... but I don't know yet if it's wired NC or NO - would be easy to change - the other terminal is there. jspencer has some of them to try on his machine - haven't heard yet how that's worked out.

I haven't got the wire to hook them up yet. Maybe this week if I am lucky. They are NO as they are wired right now, if you swap the two terminals that are close to each other they will be NC. I'm still trying to figure out the best way to mount them. May need to get some aluminum or sheet metal and make some mounts that way I can use machine screws on the switch and wood screws on the MDF.

You'll be posting mill progress pictures before too long.

gacrwell

03-19-2007, 12:32 PM

My daughter just called and said somebody delivered a box of giant puzzle pieces!

Gary

bp092

03-19-2007, 12:51 PM

I'm assuming that's your kit :D. Welcome to the club, just rent a forklift on the way home to bring it in, it weighs a ton!

joecnc2006

03-19-2007, 01:26 PM

My daughter just called and said somebody delivered a box of giant puzzle pieces!

Gary

LOL, Watchout for my popcorn ninjas as someone called them.....

Joe

bp092

03-19-2007, 01:37 PM

haha, I didn't have the luxury of fighting off mine but I hear they make a mess, by the time I got home from work all my parts were unpacked in my garage.

gacrwell

03-20-2007, 12:32 AM

LOL, Watchout for my popcorn ninjas as someone called them.....
Joe

Now I understand that. I'd love to see the machine that Joe uses to pack these. First, it grinds about one fourth of the peanuts into tiny bits, then it places a 50,000 volt static charge on them, then hydraulically injects them into every nook and cranny in the box.

Hint #1: Don't unpack in the house. Hint #2: If you ignored hint #1 be sure you have lots of time to clean up before the wife finds out.

But it seems to work. The box looked like it had been mauled by a mountain lion (really, it looked like claw marks), but everything inside was just fine. Oh, and about the forklift thing - I never tried to lift it - got a son that does all the heavy lifting; it was parked in the house when I got home.

Hint #3: My daughter suggested using dryer softener sheets to wipe off the atomic peanut bits that were madly clinging to all of the parts. Seemed to work.

Here's what it looks like on Der Tag:

toneV8

03-20-2007, 02:17 AM

Everyone is afraid his own wife.:) :)

bp092

03-20-2007, 04:39 AM

Looks good! Glad you held back the packing peanuts main line! Look forward to seeing you assemble it.

ccsparky

03-20-2007, 06:56 AM

Congratulations on your new arrival! Any cigars? :)

Look forward to seeing it come together!

I can see it now, Joe and Jay get together, redesign custom shoe hold down to hold Ninja peanuts, Joe engraves them with "Joe's Ninjas 2007". ;)

Bob

gacrwell

03-26-2007, 12:26 AM

Progress - 6 weeks

Joe's kit arrived and unpacked; test fitted the gantry box.
Completed the bearing slides.
Purchased some additional odds & ends and tools.The fit on the parts that I've tested is fabulous.

You guys were being kind at not commenting on the bearing alignment measurements that I'd made. I finally did put a fence on the drill press table to control the 0.433" dimension and it made a world of difference. The worst slide now measures half the misalignment of the best one before. I redrilled the Z-axis slides, and assembled all of them - except I find that the hardware list (and the BoltDepot order) is short by eight 5/16 x 1" bolts; what I need for the Y-axis slides. I'll have to go out tomorrow and search for full thread bolts.

Edit, next day - Ah, Home Depot had full thread 5/16x1; any longer than that and they have the shoulder, but for now, I'm good.

Also cut the threaded rods for the carriage assembly. I've been to half a dozen local hardware stores and never found more than two 72" 1/4 rods in stock at any one. Looks like I'll wind up having to stop at 3 or 4 different places to get enough. Also, even though I knew it ahead of time, I neglected to follow the tip of putting a nut on the rod before cutting it. Removing that nut after cutting opens up the threads, simplifying things later.

After having it for about two years and never taking it out of the box, I finally got a stand for my bench grinder and mounted it. Also picked up a spray gun and a gallon of Kilz primer. Gotta go find some taps; 10-32 and 1/4-20 are all that's needed right? Probably have to buy a set anyway.

Heh, after drilling all but 4 holes for the slides, I finally notice that my drill press has a work light. Duh. Hey, it was in the shadow, OK...

Earlier I'd bought a couple of cheezy corner clamps at Harbor Freight for $3 each, thinking they might be good for aligning the box assemblies. Later I found a coupon for the same clamps for $1 each, so I wound up with eight of them. Turns out they do fit beautifully, and make the box absolutely square. (Flat, not so sure.) Pics later.

Still haven't put together a PC for it. Have a good PC but was expecting to have to buy a disk drive for it. Just realized I've got a couple of 10 Gig drives here somewhere & they'd probably do. Finding them could be a problem.

vCNC schematic is still coming along slowly. Found some information on bipolar controllers & decided I'd work on one of those too, in a similar form factor/feature set. The hardest part is deciding which features should be integrated - what are commonly used; how many zillion jumper options needed. I've really only looked at Mach3; I need to survey the other popular driver software to see what they support/need.

I'll add pics when my son brings back my camera's SD card.

Gary

ccsparky

03-26-2007, 08:00 AM

Progress - 6 weeks

Joe's kit arrived and unpacked; test fitted the gantry box.
Completed the bearing slides.
Purchased some additional odds & ends and tools.The fit on the parts that I've tested is fabulous.

Also, even though I knew it ahead of time, I neglected to follow the tip of putting a nut on the rod before cutting it. Removing that nut after cutting opens up the threads, simplifying things later.

After having it for about two years and never taking it out of the box, I finally got a stand for my bench grinder and mounted it. Also picked up a spray gun and a gallon of Kilz primer. Gotta go find some taps; 10-32 and 1/4-20 are all that's needed right? Probably have to buy a set anyway.

I use a grinder to clean up the ends of the rods, by taking a little off the end at a slight angle then clean up with the wire wheel. :)

The thing I like most about using Mach3 is that so many folks here building Joe's machine use the same and it makes it really helpful when trouble shooting! It's also very nice software!

joecnc2006

03-26-2007, 09:51 AM

for a 10' 1/4" threaded rod try looking in the electrical section, they use it to hand the electrical stuts from roof lines. if they only have 3/8" use that and just drill out the holes at the ends of the router. Also you could use 1/4" x 12" carriage bolts on the Carriage slide.

Joe

gacrwell

04-01-2007, 02:20 AM

Progress - 7 weeks

glued the Z-axis carriage together.
ordered Kabel Schlepp off of ebay.Sheesh - that's about it. Wife has been away for the past month and returns on Monday so I've had to start putting the house back together, takes time.

Everything fit so well on the carriage that it'd be hard not to get it square. It would be easy to get something in backwards though, dry assemble it and make sure. I don't know if Titebond III was a good choice - it doesn't give much working time - had to scramble. The fit is so close that you can't put too much glue on the joints - if you do, it just gooshes out. I think just a fine sheen of glue, preferably on both parts to be joined, is about right. I got away with not too many drips. It was good to have the threaded rods ready (or clamps); tightening them up forced out a bit more glue.

The only place there was a bit of slop was the top and bottom pieces in their slots - they could slide about 1/16" front-to-back, so I made sure that both were fully at the end of the slots in the same direction before the glue set up.

I also found that the inside finished dimension is a hair less than 7.5" - I suspect the slots were just a bit deep. The only result is that my Y-axis bearing slides and the HDPE bearing block will have to be shortened up just a smidge. It all looks good though. Supposed to rain tomorrow, so I'm not gonna get it primered this weekend.

I saw the cable carrier working on David's video, so I started looking around. Got in a bidding war with one guy over some IGUS carrier on ebay that would have been great at the original price, but this guy just had to have both pieces that were offered in two auctions. Anyway, the next day there was this Kabel Schlepp (literally German for cable carrier, I think) stuff, 33" for $30, and the other dims looked good. I wasn't sure how much of it would be consumed in the bend radius, so I got two pieces of it to be sure. Should be here this week, will let you know if it looks like it'll work. There were several more pieces of it on ebay - search for "kabel".

We got pictures:
WOW- was walking around getting pics and went into the L/R to get a pic of the carriage box where I'd left it - and found a lamp on fire! (well, seriously smoking, anyway.) CFL bulb was arcing at its base - didn't know they could do that. The lamp was right over a blanket laying on the arm of an overstuffed chair next to the curtains. If it had dropped something burning on the blanket the place would have been gone in minutes.

Anyway, the pics:

The culprit CFL bulb; I think this was from Costco.
Here's how I drilled my bearing angles and kept the 0.433 distance constant; vice clamped to the drill press base.
Checking the bearing distance from the opposite angle face by holding a straight edge against it - the bearing should just touch the edge. Mine are about 10 mils too far, but at least all are consistent.
X, Y, and Z bearing rails with hardware installed. I've seen a couple of threads with questions on the hardware stack, I think these are right, from the angle piece outwards: X: nut, nut, bearing, lockwasher, nut. (I also added a lockwasher on the inside of the bracket, let me lock the bolt down with the first nut - don't think it'll upset anything. Y: nut, lockwasher, bearing, nut. Z: nut, bearing, lockwasher, nut.
Glued up Z-axis box, with and without nosey cat.I may still get some time tomorrow to work on the Z-axis assy and/or glue the upper/lower torsion box(s). Bedtime now and I gotta remember to turn out the lights.

Gary

erebus

04-06-2007, 03:03 AM

Probably a bit late but you might take a look at

http://cableorganizer.com/gortrac-automation/nylatrac-sp-series.htm

Not quite IGUS quality but at $11 a foot (+S&H) it's not too bad.

gacrwell

04-08-2007, 01:03 AM

Yeah, a bit late, but good to know. That's about the same price I got the Kabel Schlepp for. It's very good quality, but marginal in a couple of respects: - a bit smaller than I'd like; it'll be a snug fit for a pair of my motor cables, sensor cables, and an AC extension. But I tried it out with a couple loops of the motor cable and it seemed OK so I think it'll work out. - Also, it doesn't have the hinged link openings. All of the cables will have to be threaded thru it, before connectors are applied. A pain, but I can make it work.

Couple of pics: There's the Kabel Schlepp with the 115' of 18AWG 6 conductor motor wire, and 100' of 28AWG 4 conductor shielded. And, the Kabel Schlepp partially extended.

Gary

gacrwell

04-11-2007, 09:30 PM

Progress – 8 weeks

Kabel Schlepp arrived
Glued up both Y-axis boxes
Bought the 1/4-20 and 10-24 taps I’ll needThe Kabel Schlepp was pictured in my previous post; looks like it’ll work OK.

The cheesy Harbor Freight $3 ($1 on sale) corner clamps worked very well for keeping the Y-axis boxes straight while I glued them. I applied four clamps in a pattern to each side; leaving a few of the ribs free to glue, then just moved the clamps as I went, gluing and clamping. Pics show all.

One trivial little concern, the upper box is 1/16” longer than the bottom. I wish I’d noticed before I glued, it would have been simple to trim the longer sides. Joe, you might want to check your cut dimensions, because the bottom sides and top and bottom box skins all agree on length – the top sides are just that little bit longer. (Or is this planned and I’m missing something?) I know it’s probably not anything that would cause a problem, but I might go get a piece of 1/16” ply to shim it out even (it’s really close to 1/16" – I measure it at 70 mils). Other than that, everything fit wonderfully, of course; eyeball down any of the 1/4” rod holes and you can see every hole in succession.

It just occurred to me - I've got a router still in the box. I could cut a 1/16 deep pocket in one of the gantry uprights.

The weather this weekend was supposed to be clear, but instead it rained the whole time, so no priming to be done. But there's a pic of the spray gun and Kilz, all ready.

Finding those taps was no problem, but the drills didn't come with them and were only listed as numbered sizes (#7 and #25 respectively), and there was no finding numbered drills at Home Depot. From the tables I found, for the 1/4-20, a #7 gives a 75% thread, or a 7/32 gives a 50% thread – 13/64 is closer to the #7 and I think I’ve got one of those. The 10-24 uses #25 for 75% or #20 for 50%, and a 5/32 is midway between those, so I should be good on that too.

And another lucky find – I had given up on finding 4x8’ 1/4” MDF sheet for the X-box skins at the local places, so I had resigned to use ply. But I wandered thru the finished shelving aisle at Home Depot, and there they had 4x8’ sheets of what sure looks like MDF to me, with a white plastic finish on one side. It had a brand name, M-something, but it was only $14 a sheet.

Gary

bp092

04-11-2007, 09:48 PM

Looks like you're having fun. What you saw was likely melamine or some kind of laminate. I would look around first before doing that. Check yahoo local, someone in your area carries MDF, I'm sure of it. If you can't get 1/4" 4x8's just use 1/2" to skin each side, that's what I did along with a few others. I get all of my taps from sears, they come with drills and are fairly cheap, I believe they are all craftsman brand. What kind of spray setup do you have? Gun/compressor specs? Will make priming go by much faster. I wish I hadn't built mine during the winter otherwise I would have sprayed the parts with my HVLP turbine setup. About to upgrade to either a cup gun or a pump/pressure pot, not sure yet. (for lacquers, stains, primers/paints)

joecnc2006

04-12-2007, 08:14 AM

One trivial little concern, the upper box is 1/16” longer than the bottom. I wish I’d noticed before I glued, it would have been simple to trim the longer sides. Joe, you might want to check your cut dimensions, because the bottom sides and top and bottom box skins all agree on length – the top sides are just that little bit longer. (Or is this planned and I’m missing something?) I know it’s probably not anything that would cause a problem, but I might go get a piece of 1/16” ply to shim it out even (it’s really close to 1/16" – I measure it at 70 mils). Other than that, everything fit wonderfully, of course; eyeball down any of the 1/4” rod holes and you can see every hole in succession.

I have not noticed it, but this should have no effect on the machine because of the bearing slide design with the double rail will take up and missalignment up to 3/16 or so IMO.

Thanks, joe

jspencer

04-13-2007, 11:32 AM

And another lucky find – I had given up on finding 4x8’ 1/4” MDF sheet for the X-box skins at the local places, so I had resigned to use ply. But I wandered thru the finished shelving aisle at Home Depot, and there they had 4x8’ sheets of what sure looks like MDF to me, with a white plastic finish on one side. It had a brand name, M-something, but it was only $14 a sheet.

Gary

Gary-

If you'll notice in my pictures I used the same stuff. It is MDF with a vinyl finish on one side. It was the only stuff that I could find around here that was 1/4" MDF in a 4x8 sheet.

James

gacrwell

04-15-2007, 09:47 PM

Some of the others have described how they adjusted the U-bolts to fit, but it looks like they started with 2-1/2" bolts, which had to be adjusted to a smaller width. I bought the 2" bolts (from BoltDepot), so they had to be adjusted a bit wider to fit. I think they worked out well, and pretty easy to adjust. See the pics.

Note the bolts are narrower than the holes they need to fit in.
The bolt legs spread with just a little application of grunt -
such that the ends of the unthreaded section now match the mounting hole span.
Clamping each unthreaded section in a vice, a few jerks on a board with some weight behind it (I've got plenty of that) -
brings the legs back parallel, without damaging the threads, and now they match the span of the holes.The holes are a close fit, so it took a few taps to get the bolts through the block (after I added the bearing and hose sections), but then the legs were aligned well enough that the nuts drew them through the block with little effort. With the bearing rails installed, and the rod in place, these bolts adjust down so that just a couple of threads will remain showing on the bearing side of the block.

Gary

gacrwell

04-15-2007, 10:07 PM

What you saw was likely melamine or some kind of laminate. I would look around first before doing that.... I get all of my taps from sears, they come with drills and are fairly cheap, I believe they are all craftsman brand. What kind of spray setup do you have? Gun/compressor specs? Will make priming go by much faster. I wish I hadn't built mine during the winter otherwise I would have sprayed the parts ...

Yeah, I think it's melamine. I have looked at most of the box stores and haven't noticed -any- MDF in 4x8' but you're right, it must be around here somewhere. James used the melamine, and now that he mentions it I remember seeing that when I went to see his machine. I don't think it would be a problem as long as I didn't have to glue to the coated side - and I don't think that I have to (?).

Sears. Didn't even give that a thought. The only drawback there is that I'd have to go to.... the Mall. And I usually avoid that as much as possible. Of course I hadn't even looked... the only place a 10-24 tap is needed (I think?) is for the motor mounts, and with Joe's kit, he taps those, so I didn't even need that one. For the 1/4-20, I did have a 13/64 bit and that worked well - the HDPE sure does drill & tap easy.

The spray gun is just a cheepo from Harbor Freight, 20oz. If it'll pass the Kilz with any kind of an even spray I'll be happy. Son has a 30gal upright compressor that should be enough air to spit it out.

Gary

bp092

04-15-2007, 10:21 PM

30gal will be plenty. Anything less than 15/16 gallons without a pump will leave you deaf or with an overheated compressor. The mall shouldn't be bad, most sears I have seen in malls are just attached but access from the outside like a separate store all together. Melamine has probably been used but I would not advise using it. It's such a shady material, I'm really suprised so many people use it for mid range cabinetry interiors sometimes. If you do, watch your fingers cutting it, edges get razor sharp!

gacrwell

04-15-2007, 11:24 PM

Progress - 9 weeks

Glued together the gantry sides.
Assembled the Z-Axis bearing assembly.Sigh. Doesn't seem like much. I never seem to have any weekday time, and weekends always have some other jobs that take up much of my play time.

The gantry side gluing was every bit as messy as I expected. I'm going to leave them clamped up 'til next weekend at least. Before I do anything else with them I'll drill holes for the extra y-axis threaded rods and the extra side support that everyone seems to be adding. I've seen some 1" steel box tube that looks like it might work well for that.

The only problem I had with the z-axis bearing assembly was with the backlash nut supports. After I drilled the supports, taking care to keep the ends flush with the end of the backlash nut, I notice that they were about 1/64" shorter than the nut block, so the other end wasn't flush. I didn't notice that the nut block can only mount one way, and naturally I had the wrong end flush. (In the first pic you can see the mismatched edges.) That would have left the nut at an angle of a degree or two (see pic - blurry, but it shows the angle that would have resulted). I straightened it up by shaving off the nut block on the disk sander. Part I don't like about that is that it effectively altered the position of the lead screw relative to the bearing rods. I'll have to keep this in mind when mounting the motor and screw bearing - I might have to add some play in the motor/bearing mount, or shim up the backlash nut and supports.

Other than that, the z-axis assembly went really well. See previous post about the U-Bolts. You'll notice extra holes in the bearing angles, there because I re-drilled the holes for better alignment & didn't want to toss the angle material; thus my bearing bolts are offset differently, but I don't see that it makes any difference. Also note I had to place a washer under each angle hold-down bolt, because the 1-1/2" bolts were extending thru the block, and there's no cutout for them on the router mounting plate - I think I got my slots on the angle a little deep. But there's no problem there as now the bolts don't extend out the back and the rod clears the bolt head OK.

All I have left on this piece is to cut off the ends of the U-bolts. I have tested the fit on the individual rods and get 6-bearing contact on each without much drag - we'll see how that works out when I have both rods mounted in the carriage (waiting for painting). Maybe I'll give that a trial fit this week anyway.

edit: Oh, and like everything else the fit on Joe's kit pieces was fabulous. If I had looked ahead and noticed the nut support issue it wouldn't have been a problem.

Didn't plan on painting today because forecast was for probable rain - naturally was perfectly clear, warm & sunny; too windy though anyway.

I've been keeping an eye out for a good price on some solid-state relays. I actually have a good circuit for one that I was going to put on the vCNC controller, but decided it's not worth the trouble at the price that you can get the SSR bricks. This is the best I've found: http://www.mpja.com/productview.asp?product=16596+RL up to 240V, 18A, 3-15V control, zero-crossing, for $9. The link on that page for the data sheet is busted, but it's here on the Crydom site: http://www.crydom.com//userResources/productFamilies/22/crydom_ez.pdf If that's more than you need, there's this one, 10A @ 240V: http://www.mpja.com/productview.asp?product=7472+RL for $5 (but I haven't looked at it's data sheet, and, it's 'used').

Also at MPJA, this looks like a killer deal to get logic and fan voltages if you need them (and don't have an old PC supply around): http://www.mpja.com/productview.asp?product=11687+PS Cheaper than any set of regulators you could put together, and, a lot smaller than a PC supply. I have regulators on the vCNC schematic, but giving that a rethink. I'll probably be ordering that supply and a couple of the SSR's; will report what I get.

Gary

gacrwell

04-24-2007, 09:38 AM

Progress - 10 weeks

ordered relays
cut the z-axis drill rod and acme rodAnd that's it. Rained again this weekend and I've pretty much decided to get the rest of it assembled and paint all at once.

Gary

gacrwell

04-30-2007, 01:03 AM

the solid state relays arrived, with some other stuff
drilled & tapped the router mounting pieces
test assembled the Z-axis
bought 1” square steel tube for side reinforcementThe $9, 18A solid-state relays I ordered from Marlin P. Jones arrived and they look really good: http://www.mpja.com/productview.asp?product=16596+RL (http://www.mpja.com/productview.asp?product=16596+RL) Along with the relays I got a +5V, +12V, $4 power supply to be used with a controller to be named later, and a heat sink for my HobbyCNC PRO controller. I’ll detail the heat sink in a separate post.

Earlier this week I tried a test assembly of the Z-axis rails and bearings and I found that the anti-backlash nut mounting assembly was too short – when tightened up, it bound up the lead screw (I was afraid this might happen due to the problems I had assembling the mount – see earlier post). After backing off the mounting bolts two turns the screw was free and everything moved easily. 2 turns = 100mils, so I needed a shim under the nut mounting assembly. I was going to get some 3/32 ply at the hobby shop, but I remembered some old scrap blank printed circuit boards that I had here that were .096”. It was pretty easy to cut out a ‘U’ shape and drill to fit – worked out well.

The 5/16 lock nuts for the U-bolts that were called out in the BoltDepot order really weren’t suitable – they don’t lock until you tighten them down, and by then the bearings are too tight. I wanted nylon insert lock nuts, but Home Depot was out of that size, and they were 80 cents each anyway. Someone had mentioned Fastinal in a thread here the other day, and the name sounded familiar – looked it up and there’s one here just a mile away. The one here doesn’t normally sell small stuff by the piece, but, if there’s already a partial package open they will. There was, so I got my nuts. Much nicer to adjust the U-bolts with those. I also got around to cutting off the excess length of the U-bolts.

As I mentioned earlier, I figured out that I needed 10-24 x 1” bolts for the stepper mounting, and those weren’t on the BoltDepot order either. Picked up some pan head bolts at HD, then figured out that pan head’s diameter is too large to fit next to the stepper body. Socket heads were what I needed, but HD only had them in stainless steel, so it was $5 for a dozen. Then I found Fastinal, and fortunately there was a package of those open too (the ordinary black kind); so the ss bolts will go back to HD.

So now, with all my bolts & shims taken care of, I did one last test assembly of it all. The shim looks good, so I’ve taken it all apart and it’s ready for painting.

We gots pics:

Solid state relay and cute little power supply
Solid state relay - 18A thru those faston lugs
the back of the relay - it'll need to be mounted on a heat dissapative surface.
the shim installed for the backlash nut mount
the complete Z-axis assembly, finished (except for the obvious recto-cranial inversion) and ready to take apart for painting.

gacrwell

04-30-2007, 01:07 AM

I haven’t fiddled with my controller yet, because I didn’t want to put power on it without a heatsink on the driver chips. Since I bought it a few months ago, I’ve been looking for a heatsink that would be smaller and more effective than just a solid bar (which is what is recommended). Never found exactly what I wanted, but when I was ordering the solid state relays, the same place had this one that looked promising: http://www.mpja.com/productview.asp?product=15546+HK (http://www.mpja.com/productview.asp?product=15546+HK) @ only $2.50.

It’s almost exactly the same length as the HCNC board so it doesn’t have to be cut to length; the height is good, and anything finned will work better than a solid bar. However the board layout was never intended for the thickness of a finned heatsink; there are components too close to the back of the driver chips.

To make it fit, it was necessary to remove three fins from one edge of the heatsink. The remaining fins would then extend above the other board components. It would be easy to remove them with a handy end mill, but I had none. Assorted drilling, grinding and filing got the job done though. The heatsink already had a half dozen mounting holes drilled in it, but they won’t interfere with drilling holes to fit the driver chips. I haven’t got it mounted to the board yet, but it looks like it will work very well.

Even with the fins removed, it has about double the surface area of a 2" wide solid bar.

Gary (Hey! The second picture is actually also a picture of... my thumbnail - so it's a thumbnail thumbnail attachment. Sorry, it's late.)

Pictures: The unmangled heatsink with the HCNC PRO board, and the heatsink missing a few fins.

gacrwell

04-30-2007, 01:13 AM

After my wife had gouged her leg on the sharp end of one of the threaded rods that was sticking out of the Z-axis box, I got to thinking about the ends of those rods. They could be a nuisance, gouging material, snagging clothes – I thought about cap nuts, but you have to have the length within a pretty close tolerance to use those. What I wanted was a nice rubber cap. I knew Caplugs had vinyl caps that might work – I ordered a selection of samples – they had arrived a couple of weeks ago, and I found one that fits nicely (0.375” I.D., ½” long), but they only sell them in a package of 1000 for $50 (and that was the ‘mini’ pack). Found the same thing a couple of other places, but not in less than packages of 1000 (but as low as $35).

I finally took a look at McMaster-Carr. I’ve known about them for years, but never ordered anything there. Sure enough they had what looked like the same caps, and only $3.50 for a package of 100. Perfect! McMaster product number 9753K39.

But on their web site I didn’t find anything re their shipping charges, minimum orders or anything, so I thought I’d just go through the order process until it listed the charges – since I wasn’t going to order then, I didn’t want to enter a cc number so I just checked ‘invoice’ and went ahead. Surprise! The next screen said “Thank you for your order.” Wait a minit – there was a “cancel order” button so I clicked that and got a “Your order has been cancelled.” response. Whew... Next day I got an email – “Your order has shipped.”

Good thing I wasn’t experimenting with an item number for a backhoe or something. Fortunately I had selected the number for the caps I wanted, and the shipping was only ~$4. They arrived the other day, and it looks like they will work. They stretch and snug on the nut pretty nicely, and if you twist and press harder, the edge can be forced over the lockwasher too. They’ll look pretty spiffy against a painted surface, and I think they’ll stay on with normal use (a drop of adhesive might ultimately be necessary to keep them on with vibration).

Gary

joecnc2006

04-30-2007, 07:46 AM

I haven’t fiddled with my controller yet, because I didn’t want to put power on it without a heatsink on the driver chips. Since I bought it a few months ago, I’ve been looking for a heatsink that would be smaller and more effective than just a solid bar (which is what is recommended). Never found exactly what I wanted, but when I was ordering the solid state relays, the same place had this one that looked promising: http://www.mpja.com/productview.asp?product=15546+HK (http://www.mpja.com/productview.asp?product=15546+HK) @ only $2.50.

It’s almost exactly the same length as the HCNC board so it doesn’t have to be cut to length; the height is good, and anything finned will work better than a solid bar. However the board layout was never intended for the thickness of a finned heatsink; there are components too close to the back of the driver chips.

To make it fit, it was necessary to remove three fins from one edge of the heatsink. The remaining fins would then extend above the other board components. It would be easy to remove them with a handy end mill, but I had none. Assorted drilling, grinding and filing got the job done though. The heatsink already had a half dozen mounting holes drilled in it, but they won’t interfere with drilling holes to fit the driver chips. I haven’t got it mounted to the board yet, but it looks like it will work very well.

Gary (Hey! The second picture is actually also a picture of... my thumbnail - so it's a thumbnail thumbnail attachment. Sorry, it's late.)

Thats a good find for the heat sink, will help a few people out, I may get a couple myself.

Thanks, Joe

gacrwell

05-08-2007, 02:20 PM

Another slow week. All I did was to seal the edges of the MDF on the components I've assembled so far, and sand them down a bit in preparation for priming. The water/glue mix that I've seen recommended for the edge seal seemed to work well.

Also cut the 1" square tube to length for the gantry reinforcement. Looks like it will work well.

I've made up a 'parts list' that I'll post in the 'mods and additions' thread.

Gary

GunPilot

05-13-2007, 12:35 AM

Gary, you do a great job of providing information and links as you go along. You have already saved me a ton of time and trouble. Thanks a bunch!

BTW, spent a little time in Boise and Meridian a while back. I thought it was cool having a race track right in the middle of town. I still have my Meridian Speedway T-shirt ;)

-George

(AZ)

gacrwell

05-16-2007, 12:19 AM

Thanks George, glad I could help. Unfortunately I'm going so slow that it looks like you'll soon be way ahead of me.

My brother used to drive at Meridian Speedway, spent quite a few Saturday nights there, gosh, in the '60's.

Gary

gacrwell

05-16-2007, 12:43 AM

bought the 3/4 and 1" pipes
made up a mount for pipe turning
cleaned out the box for power supply and controller
mounted controller heatsink
secured bearing box adjustment nuts
prep for paintingI'd been checking out the pipe racks at the stores for several months now, keeping an eye out for the smoothest pipes - I noticed something that I haven't seen mentioned here. There are the galvanized pipes, and I've seen a few good ones; most not so good. And, the black painted pipes; mostly pretty rough, dinged up paint - I dreaded the mess that sanding down the paint would make. But, there was a third type there occasionally. There's a black pipe that is unpainted. In the same bins as the black painted pipe, marked and priced the same; just no paint. I have no idea if it's called something different; I'd have no idea how to ask for it specifically. But, except for the occasional scratches and dings, it's very smooth. Once I get the tape residue from the label off of the 3/4" I won't need to turn them at all, just take out a few small scratches (or align the pipes to avoid them). The 1" pipes have a few more significant scratches, so I am going to try turning them, but I don't think they'll need a lot of work.

I made up a really simple adaptor to chuck the 1" pipes - just a pipe cap with a 1/4" hole drilled in the center. Bolt, lockwasher & nut in the hole and its done. See the pic. There's a little bit of runout so I might try filing the hole to get the bolt centered a bit better, but it's not too bad as-is. I've got a very old little hobby lathe that's little more than a mounted variable speed drill that I can clamp to the workbench to chuck this into. I'll mount some small castors to to a 2x4 to rest the other end of the pipe.

Gutted the old PC box that I'm putting the power supply & controller in. It was an old STD bus computer; even more obscure than an S-100. It looks like everything will fit, but I'll have to drill some holes to get air through the power supply, it'll be tight. Taking the box apart yielded the 4-40 bolts I needed to mount the heatsink on the Hobby CNC controller, so I got that drilled and mounted.

I'd already pressed in the bearing box adjustment nuts, so I wasn't planning to take them out to use T-nuts. (To avoid accidentally knocking out the nuts, or stripping their mounting later.) Instead I sprayed some bolts with WD-40, threaded them into the nuts, and added glue to the remaining cavity. Then, I cut out some 1" square pieces of fiberglass (more leftover pc boards), drilled a 5/16" hole in the center, and glued them over the nuts as well. I think it'll be pretty hard to get those nuts loose now.

The place I work, uses HDPE to build semiconductor wafer handling stations - I don't know who or where, but I know they do. Also, out at the back of the plant, there's a 'desirable trash' area. Usually it's just empty boxes, crates and pallets - most of the wood is poor quality and has too many nails and staples to be useful. But, I'd heard that sometimes there are HDPE scraps there too. Bingo - today I stopped for the first time in a long time and found a couple dozen pieces of HDPE - the largest only about 5"x15", but most plenty big enough to play with. Various thicknesses. I'm going to have to make that a regular stop. Ok, now looking closer, this is not HDPE - must be PVC, that's cool too.

All of the gantry parts are now ready for priming/painting, this weekend, for sure.

Oh - and I just got some E-switches on ebay, a pair of really slick ones, more elaborate than I'd intended. Pics when they come in.

joecnc2006

05-16-2007, 07:49 AM

I had never seen those pipes here local at the hardware stores, all i see have a coating on them, you did get lucky and avoid the sanding down.

Joe

fade2black

05-21-2007, 11:12 AM

Those are the same pipes I have and all they had in the bins at my local HD. Maybe they are in the process of changing vendors? I thought those were the painted one's, good to know they aren't! :)

gacrwell

05-21-2007, 02:21 PM

Those are the same pipes I have and all they had in the bins at my local HD. Maybe they are in the process of changing vendors?... :)

Could be. I've seen them at both HD and Lowe's, but always in with a mix of the painted pipes. I'm wondering if there might be an issue with corrosion in the long term, but then, there would be with the others too, after sanding off the paint. They seemed to have a light coating of oil on them.

Gary

gacrwell

05-21-2007, 11:28 PM

Drilled & tapped X-axis adjustment box
Fitted X-axis adjustment block and rails
Drilled gantry sides for extra support rails and allthread
Primed the inside of the Y-axis boxes
Finished gluing the Y-axis boxesThe X-axis bearing adjustment block needed to be sanded down a bit to fit in the box, now, of course, its a bit too small and there is some vertical play in it. This could wind up tilting the entire Y-axis so I'll have to pay attention to it - I'm hoping I can add some shims to it to make it match the vertical position of the bearing rails on the other side. Next weekend after the Y-axis boxes are dry, I'll be able to test assemble the gantry.

Using the 1" square steel tube as the side support still looks like it will work well. The top uses one of the upper Y-box threaded rods, and the bottom uses one of the rods that I added thru the bottom Y-box. Each tube is also bolted to the side at three points in between those two rods. Besides the two added rods in the bottom box, I added holes for two rods near the middle of the sides.

Yes, I'm that anal that I primed the inside of the boxes before closing them up. I used a foam roller and brushes, and wasn't terribly happy with the result - fortunately it's on the inside. It could have been that the Kilz primer doesn't work well with foam brushes, or that I used cheap foam brushes, or that I am just a painting Klutz; possibly all three. Anyway it didn't cover well, and it took just too long - I didn't think just the inside would take so long, but it would have been faster to deal with the spray setup & cleaning. Next time I paint it will be to prime all of the gantry components and I'll give the spray gun a shot.

I was glancing at ebay, and wondered if there were ever any good prices on the Hitachi router. There is one place there that appears to routinely sell it for $99, but they charge $30 'shipping', so it's no bargain. I did notice one for $89 though, and took a closer look. NIB, and surprisie, it turned out to be at a local pawn shop - no shipping. So I bought it. You may recall that I started this thread by buying the router at Lowes, so for the moment I've got two, and apparently, no receipt for the first one. But, they will take it back for store credit, and, we're in the process of buying wood for my granddaughter's swing set; so it all works out.

gacrwell

05-22-2007, 03:07 PM

Edit: Never mind Joe - I see later in that thread that others just tapped 5/16", so that's what I'll do.

Gary

Say Joe, in this post:
http://www.cnczone.com/forums/showpost.php?p=240717&postcount=49
you've got the four bolts thru the router mounting plate threading into the Z-axis bearing plate, but on mine Z-axis plate, those holes are drilled 1/4", not tapped. I can't take a bolt the other direction because the holes are too near the bearing mounting bolts on that side. So my question is, do I just leave it with the four outer bolts that go thru the router mounting pieces, thru the plate, threaded into the z-axis plate; or, should I drill and tap out those inner four holes to put 5/16" bolts in those holes?

Gary

gacrwell

06-03-2007, 12:36 AM

e-switches arrived
fitted Z-axis adjustment block and rails
drilled & tapped router mounting plate & z-axis block for extra 5/16" bolts
countersunk holes for side support rail bolts
found springs for AB nuts
several hours of sanding to prep for paintThe e-switches I got on ebay look good; two for $18, shipped, so I think that was an OK deal - I've seen similar switches other places for $12-$20 or more each. These are the type that latch when you press them, you then turn to release. Still wondering where I'll mount them - I'm thinking maybe one on each side of the gantry, near table level. That way there'll always be one close to where things are happening.

Had to sand down the y-axis bearing block to fit into the carriage. Joe has said that due to variations in material thickness, the pocket depths can vary, which affects the inside dimensions of the carriage. In my case, I had to take the (normally 7.5") bearing rails down by 3/16" to get them inside.

Joe has also mentioned that the 4 holes in the z-axis bearing block (that are mid-way between each of the u-bolt holes) that should be 1/4" tapped may have gotten 1/4" drilled; they were in my Joe's kit anyway. So, to use those holes, they have to be tapped 5/16", and the corresponding holes in the router mounting plate drilled out to 5/16". Had to go buy another tap and some bolts, but that worked out fine.

My 1" square tube side supports will mount with threaded rods thru the boxes at the upper and lower ends, and 3 additional bolts along the length. At least one of those will be under the upper box where it would have to be countersunk, so I bought a Forster bit and countersunk all of those holes.

A lot of my running around could have been avoided if I'd bothered to stop at the local ACE hardware store. Which is particularly stupid in my case because it's only three blocks away and I drive past it on the way to Lowes or HD. Found the springs there for my AB nuts and a bunch of other odds & ends. Good selection of hardware (but still no full-thread bolts in most longer lengths), and an (almost annoying) staff that is eager to find stuff. Just a few doors down from ACE is a Woodcraft store that I'd never stopped into before. Really dangerous place. I picked up some leveling feet that I'll use for the table legs, and some small castors that I'll use to support my x-rail pipes when turning them.

One of the things I found at ACE was the inset 5/16" nuts (see pic) for the bearing adjustment blocks. Since I already had the regular nuts pressed in, I drilled new holes for these. In the pic there is one screwed in - I then figured out that they'd be even more secure if they were screwed in from the inside. These are pretty short, so I extracted the one I'd screwed in - there should be enough material to hold it secure in the same hole when I insert them all from the inside after painting. I'll only be using these on the Z-axis block, because the way I'd done the Y-axis nuts earlier, I'm pretty sure they're not going anywhere.

I'd really really planned to paint this weekend but I have to do it outside and it was really too windy (paint the car, paint the house, paint the cat; whatever's downwind). Found out that I had to go out and get an adapter for the spray gun to get it on the air hose anyway. But I did do a lot of sanding on all the gantry parts, so, in theory, it should look nice when I do get to paint it. I also finally figured out that one 16oz bottle of Titebond is not going to finish this, so I picked up another.

BTW, all the talk of the 2-start screws - sure looks like the way to go, but I've already got the original single-start so I'm going to continue to build with those. I fully expect to change over later, but after I get something running to cut some of the other bearing blocks & stuff I'll need for the 2-start.

I've figured out that there are some good XLR connectors (for motor connections), but the good ones that I've seen (7.5A/pin) cost more for a set than the (relatively expensive) CPC connectors. Still dithering. Also having second thoughts about the PC/controller boxes - the motherboard I'm going to use is already in a nice, compact case, and I have another identical one that I might be able to squeeze the power supply and controller into - they'd look nice side-by-side.

trajan

06-03-2007, 06:42 PM

I've figured out that there are some good XLR connectors (for motor connections), but the good ones that I've seen (7.5A/pin) cost more for a set than the (relatively expensive) CPC connectors. Still dithering. Also having second thoughts about the PC/controller boxes - the motherboard I'm going to use is already in a nice, compact case, and I have another identical one that I might be able to squeeze the power supply and controller into - they'd look nice side-by-side.[/COLOR][/SIZE][/FONT]

GARCWELL

I recently purchased some connectors. They were expensive but I really liked them and they were good for 30 amps.

Check the description out at my Blog

http://www.dickshouse.net/wordpress

Richard

gacrwell

06-09-2007, 12:10 AM

Painted all of the gantry components!!!
Mounted support steel tubes to gantry sides.
Test assembled carriage and Y-axis.
I’ve been threatening to get the painting done for weeks, and I finally did it. Of course after the weekends that rained or were too windy, I finally got a weekend that was record high temps – high 90’s both days (just a few days later and the highs are in the low ‘60’s). Two coats of primer on Saturday and two coats of color on Sunday. I was really tempted to try some color scheme, but finally just went with white all over – I figure I can change it easily or add some trim color later. I could throw away my $20 Harbor Freight spray gun right now and feel like it was totally worthwhile. It really laid down the paint nicely, and quickly, with control. Most of my time was spent moving pieces around between spraying and drying areas, and sanding between coats. It came out so well, that now I feel guilty about not spending a couple more days filling and sanding those really minor spots. You'll notice I get to spray outside, but it's OK; the bugs sand out real easy.

I also sanded and painted the square steel tubes for the gantry side supports, and mounted them on the gantry sides. I also popped in some black plastic end caps. With the black vinyl caps for the threaded rod ends, the total effect is really slick. In the picture below, the three bolts on the tube are countersunk on the other side; the two end holes will take threaded rods.

I completed the assembly of the carriage, everything but trimming the threaded rods to their final length. You may recall I was worried about the spacing of the AB nut mounting, and I had added a spacer to stand it off to where I thought it should be. Threading in the acme rod, it came out dead nuts on through both bearing blocks and the AB nut. I mounted the motor and chucked up the outer shaft in a cordless drill and could run the Z-axis up & down full length with no problem at all. And absolutely no detectable play or backlash. Though I said above that it was a ‘test assembly’, right now I can’t think of any reason to take it apart – call it a provisional final assembly.

Just for fun, I also dropped the Y-axis pipes into the box and stuck it into the carriage. Clamped the bearings down and it runs great end-to-end. This weekend I’ll get the whole gantry together – all I have to do is bolt stuff together and cut off the threaded rods.

Oh, although my pipes are pretty smooth, I tried sanding down a section and that looked really nice. So, I’ll also try chucking up the ¾” pipes before the gantry assembly and get them spiffed up.

On to the X-axis box...

gacrwell

06-09-2007, 12:22 AM

GARCWELL

I recently purchased some connectors. They were expensive but I really liked them and they were good for 30 amps.

Check the description out at my Blog

http://www.dickshouse.net/wordpress

Richard

I've used Anderson Power Pole connectors before - they are a standard item around amateur radio installations for 12V power. But I didn't know that they had a shell that would gang them together, that's pretty neat. A bit expensive for my tastes but I'll keep them in mind when I need more current. I think I've just about decided to order CPC connectors for the motors and mini-DIN's for switch cables.

Gary

joecnc2006

06-09-2007, 01:00 PM

Looks like it is comming along good, will be all togther before you know it.

Joe

trajan

06-09-2007, 10:04 PM

Gary, I received the AAP connectors and will take some pictures tomorrow and upload them. They are pretty slick. I am still waiting for my GECKO 203Vs. Apparently I ordered them when they were out and waiting for a new shipment. I am pretty much stalled until I get the GECKOS or Joe's KIT. I am sure he is very busy.

Richard

gacrwell

06-15-2007, 11:19 PM

Well, none, really. I got the excess rod lengths cut off of the carriage, and mounted my controller heatsink with thermal grease, and that's about it. This weekend I get the gantry together, for sure.

Gary

gacrwell

06-18-2007, 12:48 AM

Shined up the Y-axis pipes
Assembled the gantryIt was a beautiful weekend for a spin. The pipes shined up nicely. I used the bolt in the pipe cap to chuck them into the drill (I like the drum sander idea posted earlier, but I already had the pipe caps). And, I used small castors screwed into a board as the rolling end support. All worked well. As I mentioned before, these pipes have very little 'paint' on them just a dark coating of some sort - still made a mess, but not bad. Sanding them really brought out the rough spots that I hadn't noticed before. It would take a lot of turning to get those spots out, but now that I can see them I can clock the pipes to avoid them in the bearing track. I used the soft sanding sponges, though I probably should have started with a coarser grit. See the pic of the 'sanding sponge clamp'.

With the pipes and everything else ready, the gantry bolted together without a hitch. Eight threaded rods are run thru the gantry, with the two in the center, and two through the lower box. I think I've got the lower two positioned so they'll clear the X-axis acme rod. Note that the 1" square tube reinforcement is positioned to take a threaded rod in each end. As before with the carriage, the vinyl caps are really a nice touch to the threaded rod ends. I grieved over every tool mark I made in the paint, but I guess I can touch it up later. Not much else to say - everything fit and looks to be aligned well. I can see that I'll need to add a bit of play in the Y-axis AB nut mounting, to get the rod lined up, but that's it.

ccsparky

06-18-2007, 01:02 AM

Gary,

Those pipes look really nice and shiney! :cool:
I like the sponge clamp, great idea!
Your machine is coming along very nicely, thanks for all the tips!

Bob

biotech1

06-19-2007, 12:15 AM

Those pipes are SHINY.... what grit proccess did you use to get that shiny--

gacrwell

06-24-2007, 11:29 AM

Those pipes are SHINY.... what grit proccess did you use to get that shiny--

Really, just those sanding sponges - they're only marked coarse/fine/medium, and I only used the coarse, which maybe feels like about 180/120. I think next time (especially on the larger pipes) that I'd start out with some coarser paper - it relly took longer than I wanted with the 36" pipes - probably almost an hour on each.

With the 'sponge clamp' though, I was really getting a lot of sanding contact area with a pretty good pressure. I could also modulate the pressure by twisting the clamp. Much of the time I had the pipe lifted off the rollers, using the sponge clamp as the 'end bearing'.

Also recall that I started out with black pipe, but not those with the heavy black coating - the ones I found had a thin, almost translucent, black coat.

BTW, I really like those sanding sponges for nearly all the spots that I can't get a powered palm sander into. They get into corners very nicely and seem to last forever. Cheap when they're on sale at HF - don't recall the package price, but do remember that it comes out to only 25 cents each.

Oh, and here's a thought - cut out a couple of pieces of plywood to the shape of ping-pong paddles, but with square 'paddles' a bit larger than the sponge. Pocket each out ~1/4" to hold a sponge, then hinge the paddles together at the top edge. That gadget would hold the sponges flat lengthwise against the pipe, and you would control the pressure by squeezing the handles together. The hinge end would need a spacer so that the paddles would clamp down ~flat on the pipe. I think I'll have to make up something like that before I start the big pipes.

Gary

gacrwell

07-16-2007, 04:18 PM

It's been a few weeks since I've made a progress report, but I haven't gotten much done in that time. A few health issues have intervened, and the place I work just laid off a thousand people, so there's been other stuff on my mind.

However, I finally did get around to loading up Mach3, and wiring up my Y and Z axis motors and HobbyCNC controller. Also rewired the power supply to give 35V. First time I powered on, no lockup. DISSAPOINTED! Didn't take long to find the problem. The colors on the motor wires (Keling) matched one of the color patterns listed on the HobbyCNC instructions so that's what I used - I thought there would be -some- commonality, since most of the motors probably come out of the same plant in China anyways. Anyhow, looking up the correct data sheet showed that the motor wires were completely different - rewired and everything started working as advertised.

Just jogging it back and forth, up/down, it doesn't have any problem with 60 ipm; with no adjusting, no lubrication; I still have the original 10-turn single start leadscrews. Very smooth too. I can probably get a few more volts by trimming up the power supply, and I think I can tweak the current up a bit too.

As-is, it stalled when I tried 80 ipm. I'm wondering though; it seemed to stall only when first starting after a pause. The HobbyCNC reduces current after 10 seconds, and doesn't restore it until after steps are detected. I'm wondering if that's the issue. I've noticed that Mach3 has a CurrentH/L output, but I don't see anything about it in the documentation. I'm guessing that if I used that, it would do a better job of controlling the current. It looks like the HobbyCNC would be pretty easy to modify for that. I haven't got the controller in a box; it and the power supply are sitting out where I can fiddle with them, so I might give that mod a try after I figure out if the Mach3 H/L control works like I think it does.

So now I seem to have an excellent 1.5D router, so I can do some wicked variable-depth straight cuts. Guess I should get started on that X axis box.

Gary

joecnc2006

07-16-2007, 05:43 PM

any pictures of PSU and specs?

Joe

Jay C

07-17-2007, 10:45 PM

As-is, it stalled when I tried 80 ipm. I'm wondering though; it seemed to stall only when first starting after a pause.
Called slippage and it means your acceleration it too high. Tweak then acceleration ramp in motor tuning.
Jay

gacrwell

07-23-2007, 12:26 AM

Last week when I was fiddling with the Mach3 motor tuning, it would stall at 80 ipm. Today, I swear all I did was tweak the voltage up from 35 to 38V, and now the Y-axis jogs at 150 ipm, no problem. And the Z is running at 120 ipm, also up from 60. I can hear the Z-axis hit a resonance when it stalls, so I might try a different microstep with it and see what that does.

After that adjustment and test, I also got around to drilling some Acme nuts for 10-24 set screws (I remember when they were called 'grub' screws), so I could lock down the tension on the leadscrews. I'm sure dumpster clamps would be cleaner, but I didn't want the expense since I know I'll eventually change these to 2-start anyways.

I was able to 'air cut' the roadrunner sample, YZ-axes only, no problem.

You can see my old scope in the pics; I'd forgotten the limitations of an analog scope - used to the digital ones at work. But it did show me something I wanted to know. Mach3 has a Current High/Low output, and when enabled, it functions just as you'd expect it would. It goes to 'High Current' before any step activity, and drops to 'Low Current' when done. The current reduction function on the HobbyCNC goes to high current after the first step starts, and low current 10 seconds after the end of step activity, independently on each axis. Looks to me like it would be much cleaner to use the Mach3 output. I'm going to modify my HobbyCNC board to do so; will let ya know how that works out. That's why I've got everything 'hanging out' for the time being - I'll get it in a box when it's all tweaked up the way I want it.

Joe asked about the power supply: It's an old PowerOne 2KW chassis with three plug-in output modules. It probably cost about a kilobuck new, but I pulled it from some old test equipment that was literally going to the dumpster. From the pic, the leftmost module is the AC input. Next is a dual 15V, 15A module. I tried putting these in series, but that didn't work, within a single module they aren't isolated from each other. I could possibly put them in parallel, but there's no need at the moment, 15A is plenty. The next module is a single 15V, at 33A; and the last is 5V at 80A. So the hook-up now is one of the dual 15V, the single 15V, and the 5V, in series, for a total of 35V at 15A. I tweaked two of the module's trims up to get 38V. I could probably get another volt or two if I wanted.

gacrwell

07-31-2007, 11:40 PM

Finally, I jumped on the X-box assembly. I've been dreading this, because I don't have a flat workbench, a flat floor, or even a flat patch of concrete anywhere that I can trust. Add to this, I don't have a brad nailer that others have used, or even a set of pipe clamps.

So after some thought, I just decided to build it 'in air', which is pretty much what I did with the smaller boxes. No flat surface, using just my little 99 cent corner clamps and other small clamps, on a flimsy, plasitc-top, too-short folding table. I knew that the only way this could work was with frequent, multiple alignment checks.

Those checks included: check fitting the pipes in their positions on the cross ribs; bore-sighting down the threaded rod holes in the cross ribs; flatness checking with a 48" level; and twist checking by stringing thread from corner to corner of the box, checking for rib-to-thread gaps and looking for the threads to touch at the crossing point. Not shown is the carpenter's square that I also used. I did all of this, a lot; always after each gluing step. Come to think of it, it's not a bad idea to make those checks anyway, even if you have a guaranteed flat building surface.

I've also noticed that there aren't really any 'instructions' per se, for the box assembly. Everybody just 'knows' how it goes together. However, I've also noticed that a few people have had, ah, issues, with the assembly. So, I'm going to document my x-box assembly process in full, excruciating detail. That is not to say that this is an optimum, or perhaps even rational assembly sequence; it's just the way I did it. YMMV.

Of course much of my gyrations won't apply if you have a trusted flat surface - I suggest you use it. Also, if you're not building from a Joe's kit, you probably have cut the long ribs in single pieces, rather than the two-piece ribs that come in the kit. Many of my steps deal with those rib sections.

The parts - just to get things clear, I'll detail the nomenclature I'm using for the box components. Again, this is Joe's kit, so the long ribs are in two sections:

Cross-ribs: There are eight of these, all identical. Note that each has a 'long' end, and a 'short' end, referring to the length of the pipe supports that extend past the outer long rib notches. The short ends allow room for the gantry adjustment box on that side.
Long ribs: There are four of these, all identical. Each has one end with a full-deph notch, and one end with a half-depth notch. The ends with the full-depth notch will mate with the cross-ribs at the ends of the box; the half-depth notches will join with the long rib extension pieces.
Long rib extensions: There are four of these, all identical. They also have full and half-depth notches, used just like those on the long ribs.
All of the notch spacings on all of the ribs are identical, so there is no particular required location for any rib.
At this point of building the box, there is no differentiation between ends or sides - either end could be the motor mount end, and either side could be the working surface. The only asymmetrical feature is the shorter pipe supports on one side, that will be the gantry adjustment box side.To work - see pics

Note the ends of the long ribs and their extensions - on each, one end is a full-depth notch, and the other end is a half-depth notch. The long ribs and the extensions are matched together so that the half notches will fit together to form a full notch.
Note that you can't just lay the pieces on a flat surface for assembly; the notch for the surface skins will prevent the cross ribs from mating fully.
Proping the long ribs up on the unused pieces allows the cross ribs to fully engage.
Working outside in 100+ degree heat makes me careless (read: stupid). Here I've already positioned a mistake - thankfully before gluing - one of the long ribs is backwards, because I've got a half notch and a full notch on the near ends. See the other mistake? I've also got one of the cross ribs backwards - note that I've got a 'long' end and a 'short' end on the same side; they absolutely must be placed identically. Really, I did not place these this way to make a point; I was ready to glue them this way. I decided the great (hot) outdoors wasn't such a good idea.to be continued...